Have you ever looked at a 12-ounce bag of coffee and wondered how many cups it’ll provide? You’re not the only one. Whether you’re stocking up for the week or camping out, knowing how far that bag will take you can be the make-or-break factor. The answer isn’t one-size-fits-all—it depends on your cup size, brewing type, and strength level desired in your brew.
Understanding the Basics: Coffee and Cup Size
A 12-ounce bag of coffee is 12 ounces, or about 340 grams (since 1 ounce is 28.35 grams). That’s where it starts. But how many cups you get depends on how much coffee you put in each cup and how you measure a “cup.” In coffee culture, a standard “cup” is typically 6 ounces—think of it as the size most drip coffee makers brew. However, many of us pour coffee into 8-ounce mugs or even larger 12-ounce tumblers. For this article, we’ll focus on the two most common sizes—6 ounces and 8 ounces—to keep things practical.
The amount of coffee you use in each cup matters too. The Specialty Coffee Association (SCA) recommends a brewing ratio of 1:16 to 1:18—1 gram of coffee for every 16–18 grams of water. For ease, we will use 1:16, a good middle ground that gives a balanced cup. Let’s calculate now.
Calculating for a 6-Ounce Cup
A 6-ounce cup holds about 177 milliliters of water, which weighs about 177 grams. By the 1:16 ratio, you’d have roughly 11 grams of coffee per cup. Let’s be simple and estimate that down to 10 grams—a typical amount for a standard brew. With 340 grams in a bag, divide by 10 grams per cup, and you’ve got 34 cups. That’s right—a 12-ounce bag makes roughly 34 six-ounce cups of coffee. This is the number you’ll often see hinted at on coffee packaging, assuming a smaller cup size and a moderate strength.
Calculating for an 8-Ounce Mug
Most of us don’t sip from dainty 6-ounce cups all day—8-ounce mugs are more the norm. An 8-ounce cup is about 237 milliliters, or 237 grams of water. At the 1:16 ratio, that calls for roughly 15 grams of coffee per cup. Divide 340 grams by 15 grams, and you get 22.67 cups. Let’s call it 22–23 cups to allow for slight variations. So, if you’re using an 8-ounce mug, a 12-ounce bag will give you about 22 to 23 servings—enough for a couple of weeks of daily coffee for one person.
Does Brewing Method Affect the Count?
Your brewing method can modify these figures slightly. For drip brewing or pour-overs, the 10-gram (6 oz) or 15-gram (8 oz) approximations are acceptable. However, if you are brewing a French press, which will need a more concentrated ratio like 1:15, you would use 11–12 grams for a 6-ounce cup (roughly 28–31 cups) or 16 grams for an 8-ounce cup (roughly 21 cups). Espresso is a different beast—each double shot (2 oz) takes 18–20 grams of coffee, so a 12-ounce bag would only produce 17–19 shots, not cups. For most home brewers, though, drip or pour-over is the standard, so the 34 (6 oz) or 22–23 (8 oz) range is correct.
Adjusting for Taste Preferences
Not everyone follows the SCA’s golden ratio. If you like your coffee less concentrated, you can use only 8 grams for a 6-ounce cup, so that 12-ounce bag will last you about 42 cups. Bolder is your taste? Use 12 grams per 6-ounce cup, and you will have about 28 cups. An 8-ounce cup has a light coffee of 12 grams making it 28 cups, but 18 grams heavy cuts it to 19 cups. The beauty of coffee is its versatility—your perfect cup can alter these numbers, but the math gives you a reasonable working estimate.
Practical Takeaways
So what’s the real answer? For an average 6-ounce coffee mug, calculate about 34 cups from a 12-ounce bag—ideal if you’re hosting a small gathering or serving smaller portions. For the more common 8-ounce mug, you’re looking at 22–23 cups, which suits solo drinkers or a household with moderate coffee habits. If you’re a one-cup-a-day person, that’s three weeks of mornings covered. Share it with a partner, and it’s still over a week of caffeine bliss.
These are weight estimates in terms of whole beans or pre-ground coffee, not volume—scoops may vary, but 2 tablespoons worth of grounds is roughly 10 grams, which matches our guesstimates. And if grinding freshly bought beans, the yield will still be the same as long as you weigh them before grinding.
Conclusion
A 12-ounce bag of coffee is a trusty companion, making between 22 and 34 cups depending on how you use it. Whether you’re whipping up a quick 6-ounce pick-me-up or adding to an 8-ounce cup to sip slowly, now you know exactly what you’re getting. The next time you grab that bag off the shelf, you can map your coffee journey with assurance—how many cups will it fuel for you? If you have a unique brewing method or cup size in mind, alter the math and make it your own. Enjoy brewing!
